The present invention relates to the field of telecommunications and, more particularly, to the efficient routing of data packets and data streams to the correct applications.
The Internet and telecommunication world has developed several data protocols to be carried over point-to-point links for different kinds of purposes. There is, for instance, the PPP protocol for delivering network layer data over point-to-point links, the H.324 Standard for delivering multimedia data, etc.
On the other hand, modern multimedia terminals and communicator-style devices are being developed that are potentially able to handle many different kinds of data protocols carried over point-to-point links. An example is the Nokia 9110 Communicator.
The problem is that there is no common protocol or format that these protocols, for instance, PPP and H.324, may share. This makes it difficult to implement a data parser or recognizer that routes the incoming data to the correct handler in terminals that can interpret several data protocols, such as PPP and H.324.
The PPP protocol allows a negotiation of the used network protocol in the Network Control Protocol (NCP) phase of the PPP protocol. However, the PPP enforces that the payload protocol data will always be carried inside High-Level Data Link Control (HDLC) framing.
It would be easier to implement the routing of the data stream to the right handler if there were some way to tell what protocol data is coming in the data stream in order to allow transmission using the identified payload protocol, i.e., without enforcing the payload protocol data to be carried inside HDLC framing.
According to a first aspect of the invention, a method for sending information from a sending terminal through a network to a receiving terminal comprises the steps of sending a selected number of prefix protocol packets indicative of a payload protocol of a packet to follow through said network to said receiving terminal, and sending said payload protocol packet to said receiving terminal immediately after sending said selected number of prefix protocol packets. The prefix protocol is an agreed-upon protocol such as HDLC. The payload protocol will be one of various possible protocols to follow the prefix protocol, such as H.324, PPP, or the like. In this way, the payload protocol can be different from the prefix protocol and does not have to be carried inside some other protocol.
According further to the first aspect of the invention, the sending of said protocol packets continues up to said selected number unless a message is received from said receiving terminal indicating either that the payload protocol is not supported in the receiving terminal followed by halting said sending of prefix protocol packets, or that the receiving terminal is ready to receive said payload packet followed by said sending said payload protocol packet after sending a number of prefix protocol packets less than said selected number.
According still further to the first aspect of the invention, a terminal for sending information through a network to a receiving terminal comprises means for sending a selected number of prefix protocol packets indicative of a payload protocol of a packet to follow through said network to said receiving terminal, and means for sending said payload protocol packet to said receiving terminal immediately after sending said selected number of prefix protocol packets.
Still further according to the first aspect of the invention, the terminal wherein sending of said protocol packets continues up to said selected number unless a message is received from said receiving terminal indicating either (1) that the payload protocol is not supported in the receiving terminal followed by terminating sending of further packets, or (2) that the receiving terminal is ready to receive said payload packet followed by said sending said payload t protocol packet after sending a number of prefix protocol packets less than said selected number.
According to a second aspect of the invention, a method of receiving information in a receiving terminal through a network from a sending terminal comprises the steps of receiving a selected number of prefix protocol packets indicative of a payload protocol of a packet to follow after said selected number of prefix protocol packets for synchronizing on said prefix protocol packets and for readying a handler of said payload protocol packets, and receiving said payload protocol packet.
In further accord with the second aspect of the invention, the method further comprises the steps of determining before receiving all of said selected number of prefix protocol packets that said payload protocol is supported in said receiving terminal, and sending a message from said receiving terminal to said sending terminal that said payload protocol is supported in said receiving terminal for causing said sending terminal to stop sending said prefix protocol packets and immediately sending said payload protocol packet.
According further to the second aspect of the invention, a terminal for receiving information through a network from a sending terminal comprises means for receiving a selected number of prefix protocol packets indicative of a payload protocol of a packet to follow after said selected number of prefix protocol packets for synchronizing on said prefix protocol packets and for readying a handler of said payload protocol packets, and means for receiving said payload protocol packet.
Still further according to the second aspect of the invention, the terminal further comprises means for determining before receiving all of said selected number of prefix protocol packets that said payload protocol is supported in said receiving terminal, and means for sending a message from said receiving terminal to said sending terminal that said payload protocol is supported in said receiving terminal for causing said sending terminal to stop sending said prefix protocol packets and immediately sending said payload protocol packet.
According to a third aspect of the invention, a method of communicating information between a sending terminal and a receiving terminal over a network comprises the steps of sending a selected number of prefix protocol packets indicative of a payload protocol of a packet to follow through said network to said receiving terminal, receiving in said receiving terminal said selected number of prefix protocol packets indicative of said payload protocol of said packet to follow after said selected number of prefix protocol packets for synchronizing on said prefix protocol packets and for readying a handler of said payload protocol packets, sending said payload protocol packet to said receiver immediately after sending said selected number of prefix protocol packets, and receiving in said receiving terminal said payload protocol packet.
In further accord with the third aspect of the invention, the method further comprises the steps of determining in said receiver before receiving all of said selected number of prefix protocol packets that said payload protocol is supported or that said receiver is ready to receive said payload packet followed by said sending of said payload protocol packet from said sending terminal to said receiving terminal.
Still further according to the third aspect of the invention, an apparatus comprising a sending terminal and a receiving terminal for communicating information over a network further comprises means for sending in said sending terminal a selected number of prefix protocol packets indicative of a payload protocol of a packet to follow through said network to said receiving terminal, means for receiving in said receiving terminal said selected number of prefix protocol packets indicative of said payload protocol of said packet to follow after said selected number of prefix protocol packets for synchronizing on said prefix protocol packets and for readying a handler of said payload protocol packets, means for sending on said sending terminal said payload protocol packet to said receiving terminal immediately after sending said selected number of prefix protocol packets, and means for receiving in said receiving terminal said payload protocol packet.
In still further accord with the third aspect of the invention, the apparatus further comprises means for determining in said receiver before receiving all of sale selected number of prefix protocol packets that said payload protocol is supported or that said receiver is ready to receive said payload packet followed by said sending of said payload protocol packet from said sending terminal to said receiving terminal.
These and other objects, features and advantages of the present invention will become more apparent in light of the detailed description of a best mode embodiment thereof, as illustrated in the accompanying drawing.